Using a canvas context, assuming I call beginPath then twice lineTo with x=-999, y=-999 and x=50, y=50 then finally stroke, it will draw a line from the top-left corner to the (50,50) point. During the process did the top-left outside part of the line was draw from the outside or did it was draw from the visi…
Tag: html5-canvas
How to keep drawing on canvas when scrolling?
I’m wanting to implement canvas as background for my website so users can use their cursors to paint on the webpage like this codepen: https://codepen.io/cocotx/pen/PoGRdxQ?editors=1010 (this is an example code from http://www.dgp.toronto.edu/~clwen/test/canvas-paint-tutorial/) The problem is that the c…
Promise never gets resolved in javascript
I have a asyn function in which I call another function that return a promise and also calls to another async function. Here is the code: since I have some asynchronous code to execute so I cannot invoke resolve() directly. so I use call back and the animate function itself is async doing a bunch of asynchron…
Canvas 2DPath Clip overlap pr
I’m trying to create one compound shape in canvas that masks all the content below it – i will be animating these paths so they will eventually intersect – the problem is, when they intersect, they are doing a reverse mask when the drawing overlaps. I just want one solid mask. Here is an exa…
Does canvas context2d.drawImage( webglCanvas, 0, 0 ) block until a webgl is finished rendering?
I assume the answer is “no” from my testing but I thought I’d make sure. I’m trying to draw / copy the contents from a WebGL canvas to a 2d canvas every frame and I want to know if I should wait until the WebGL context is finished drawing (which I can use gl.fenceSync to check) before …
How to make an Infinite Html5 Canvas which can be zoomed and panned?
I was working on a real time whiteboard. I want to create an Infinite canvas, which can be zoomed using the mouse wheel and panned using drag, using javascript.During the zoom and pan the items drawn on the canvas must also be affected. Is there a was to achieve this without using any external library? Answer…
Weird shape when drawing line on canvas (js)
I’m trying to make a very simple paint in JS but I have a problem when I increase the line width it create weird shape at the end of shape but not when I use a lineWidth = 1 and I don’t know where the problem come from furthermore it create space between lines while with a lineWidth=1 I don’…
My Image doesn’t take the full width of the canvas when rotated
So I was playing around the canvas and I tried rotating images loaded from my device hard disk as seen below: The problem with the code is that when I rotate the image to the inverse of its aspect ratio which is 90degree of 180degree the image gets centered and doesn’t take the full width or height as t…
Vue: Removing item from v-for list leaves behind canvas item
This is a hard one to phrase in a title, but pretty easy to explain with some setup. I have a list of components. Each component in the list looks like the following: Each component has a small canvas element that is used to display a preview of the item, It’s name, and a delete button to remove it from
Pass headers in fabric Image.fromURL function
I am using fabric.js Image.fromURL function to load the image to canvas. For now, the images are loading successfully without any issues. But now I have a requirement to pass headers for authentication purposes is there a way that I could pass headers into the “Image.fromURL” function or any other…